X-ray generating devices are incorporated in non-destructive inspection equipment.
Regarding the structure of the x-ray generating device, an electronic source (emitter), a target and a grid electrode (middle electrode) are arranged in one glass tube. To generate an electron, a voltage is applied between the electronic source and the grid electrode and the generated electron is made to hit the target by applying a voltage between the grid electrode and the target.
In addition to the X-ray generating device of a 3 electrode structure, an x-ray generating device to photograph a stereo image is disclosed in Patent Document 1.
To capture the three-dimensional image of the subject, the device disclosed in Patent Document 1 provides an x-ray tube for the left hand image and an x-ray tube for the right hand image.
The subject is irradiated from each x-ray tube alternatively, the observer views a transparent image provided by one x-ray tube with the right eye, and views a transparent image provided by the other x-ray tube with the left eye.
In Patent Document 1, to change the photography amplification of the transparent image, the distance of the pair of x-ray tubes can be varied. A rack and pinion mechanism and a ball-thread mechanism are exemplified as the variable mechanism.
Patent document 2 discloses a structure such that a plurality of cathode and a discal anode are provided in one vacuum tube. The purpose of Patent document 2 is not to gain a three-dimensional image.
The anode is comprised of a plurality of segments, x-rays with different strengths are given out from every segment by hitting the turning anodal segment with the electron beam emitted from the cathode.